Contribution of French explorers to the study of Middle Asian flora: the herbarium collections by Guillaume Capus (1857-1931)

Guillaume Capus' expeditions to Middle Asia between 1880 and 1887 resulted especially in an outstanding collection of about 3000 herbarium specimens still kept in the Paris herbarium (France). Gatherings of his first expedition were quickly identified by another French botanist, Adrien Franchet, in `Plants of Turkestan' published in 1883-1884. As part of the ongoing `Flora of Uzbekistan project', we exhaustively studied the list of plants identified by Franchet, counting 1387 gatherings. First, we updated the taxonomy for all of them and found that the plants collected by Capus represent an important diversity made of 87 families, 375 genera, and 851 species (including 74 new species and 21 new varieties described by Franchet). Second, an in-depth study of herbaria from Middle Asia led to identify seven new records of angiosperm species for three Middle Asian countries: Phlomoides agraria (Bunge) Adylov, Kamelin & Makhm. (Lamiaceae) for Kyrgyzstan, Picris strigosa M.Bieb. (Asteraceae) and Gentianella umbellata (M.Bieb.) Holub (Gentianaceae) for Uzbekistan, and Oxytropis tatarica Hook.f. & Thomson ex Bunge, Onobrychis arnacantha Bunge (Fabaceae), Pedicularis pycnantha Boiss. (Orobanchaceae), Matthiola flavida Boiss. (Brassicaceae) for Tajikistan. Third and last, we clarified all original collections localities visited by Capus, georeferenced them, and compiled a GIS-based distribution map for the species richness and collection density, thus creating a gazetter of Capus' botanical travel and laying the foundation for a gazetter of Middle Asia.

Automated summary

This study comprehensively examined Guillaume Capus' botanical expeditions to Middle Asia, focusing on his collection of herbarium specimens. The taxonomy of the collected plants was updated, revealing a significant diversity consisting of 87 families, 375 genera, and 851 species. Additionally, the study identified seven new angiosperm species records for Kyrgyzstan, Uzbekistan, and Tajikistan. Furthermore, the study clarified the original collection localities and created a GIS-based distribution map, contributing to the understanding of Capus' botanical travel and forming a foundation for a gazetteer of Middle Asia.